The invention relates to a tooth replacement comprising at least one posterior tooth having a mesial contact surface, a distal contact surface, and an occlusal surface wherein the occlusal surface comprises a least one buccal cusp having a buccal cusp tip, a lingual cusp having a lingual cusp tip, a central fissure which has at least one tooth pit and passes through the occlusal surface in the mesiodistal direction between the two cusps, a first gradient which slopes downward from the buccal cusp tip in the direction of the central fissure, and a second gradient which slopes downward from the lingual cusp tip in the direction of the central fissure.
Teeth are mainly used to crush food, but also to speak. The distinctive features of a tooth include the crown that protrudes from the gum out into the oral cavity, the tooth neck and the tooth root which may be split and which at one end has an opening for nerves. The transition between the tooth crown and the tooth root is referred to as the tooth neck.
The natural dentition which consists of upper and lower jaw consists of incisors, canine teeth and posterior teeth, i.e., the premolars and molars. The premolars are built lower and feature a two-cusped crown, the molars have broad, up to 5-cusped crown.
In tooth replacements, artificial tooth crowns, entire replacement teeth or full dentures to make sure of the masticatory function.
In the context of this invention, entire teeth and tooth crowns are referred to as teeth.
Removable tooth replacement is necessary then when a large part of the natural teeth is no longer present or even all teeth had to be removed. Today, such partial or full dentures mostly are made of plastic as a support material, in which the replacement teeth are embedded.
The common replacement teeth which are implemented in simplified form often cause unusual bite properties, wherein it is particularly unpleasant that the temporomandibular joint responds even to small deviations from the usual movement sequence, and at times also it is elected not to use the dentures for extended periods of time.
As a solution to these problems in the prior art, EP 1 010 402 B1 suggests a tooth replacement, wherein the replacement teeth are fitted with multi-functional occlusal surfaces like their real life counterparts, have an enlarged volume and have a buccally stepped tooth neck that prevents translucence of the tooth necks. Here, in theses known teeth, the cusps of the tooth crowns can have a slope that decreases from the premolars to the molars.
The disclosure of EP 1 010 402 B1 is hereby incorporated into this description in terms of the formation of the occlusal surfaces and cusp slope by express reference. The use of the teeth as described in the cited document leads in many cases to satisfactory bite characteristics. However, it has been found that these bite characteristics may be lost during the period of use of the known dentures.
FIGS. 1a-1b to 6a-6b, 8a-8e and 9a-9h show various views of a first embodiment of the tooth replacement according to the invention.
The expansion spaces that have been incorporated into the occlusal surfaces in a targeted manner according to the invention can be particularly clearly seen in the side views shown in FIGS. 3a-3b to 5a-5b and 8a-8e. 